The Koga Hospital Center for studies on sleep: Status report

Between September 1996 and January 1999 we used polysomnography (PSG) to ex amine 473 patients (involving a total of 662 records). The diagnosis was a sleep-related breathing disorder in 256 patients, including sleep apnea syn drome (SAS) in 194 patients, sleep hypoxicemia in 18 and insomnia in the ot her four. The SAS consisted of three subtypes: central apnea (CA) in 56 pat ients, obstructive apnea (OA) in 124 and mixed apnea (MA) in eight. The rat io of central apnea was relatively higher than the national average. Among the 473 patients, the most common complication was heart disease (133 patie nts) while other complications included hypertension, and respiratory and c erebrovascular diseases; Concerning the therapy for these patients, continu ous positive airway pressure therapy was the most commonly applied and was effective in each type of SAS (CA, OA, MA). Other therapies included prosth etic mandibular advancement, bilevel positive airway pressure, medication a nd ENT operations. In Koga Hospital, there are many patients with heart dis ease and/or respiratory disease. We examined those patients who presented w ith snoring and/or apnea using PSG. Among these patients, SAS was the most common sleep disorder. The relative ratio of CA was high and the average ag e was higher than those with OA.